How to migrate an application to the cloud: steps, risks and costs

Many applications still run on a server in the office or on old hosting nobody dares touch. They work, but every update is nerve-racking, backups depend on one person and growing is complicated. Moving to the cloud solves much of that, as long as it is done in an orderly way.

What you gain

• Automatic backups and a real ability to recover from a failure.
• Scaling when usage grows, without buying hardware.
• Managed security: system patches, encryption and simpler access control.
• Infrastructure as code: the environment is described and can be reproduced, instead of depending on what someone configured by hand.

Three ways to migrate

• Move as is: the application goes onto cloud machines with hardly any changes. Quick, but makes little use of the cloud.
• Adapt: some parts are swapped for managed services (database, file storage, email). Usually the best balance.
• Rebuild parts: when the application has deeper problems, the migration is used to modernise what fails most.

The steps of a migration without surprises

• Inventory: what parts the application has, what it connects to and what data it stores.
• Design of the target environment, with security, backups and monitoring from the start.
• Copying the data and full testing in the new environment, with real users if possible.
• Cut-over plan: when to switch, how long it can be down, and how to roll back if something fails.
• Closer monitoring for the first days and an orderly shutdown of the old environment.

The risks and how they are controlled

The typical problems are data that isn’t copied in full, forgotten dependencies (a service that only worked from the office IP, a scheduled task nobody remembered) and longer downtime than planned. They are controlled with a good inventory, parallel testing before the switch and a rollback plan that has been tried.

What changes in the costs

You stop buying and renewing hardware and start paying each month for what you use. Sized well, the bill is predictable; sized badly, it can grow without anyone noticing. That is why the migration should include spending alerts and a regular review of the size of each resource.

We work with Azure, AWS and Google Cloud, always with infrastructure as code, and we do a free assessment of your current infrastructure before proposing a plan with a fixed monthly fee.

Application operations and cloud migration